Book Image

The Kubernetes Workshop

By : Zachary Arnold, Sahil Dua, Wei Huang, Faisal Masood, Mélony Qin, Mohammed Abu Taleb
Book Image

The Kubernetes Workshop

By: Zachary Arnold, Sahil Dua, Wei Huang, Faisal Masood, Mélony Qin, Mohammed Abu Taleb

Overview of this book

Thanks to its extensive support for managing hundreds of containers that run cloud-native applications, Kubernetes is the most popular open source container orchestration platform that makes cluster management easy. This workshop adopts a practical approach to get you acquainted with the Kubernetes environment and its applications. Starting with an introduction to the fundamentals of Kubernetes, you’ll install and set up your Kubernetes environment. You’ll understand how to write YAML files and deploy your first simple web application container using Pod. You’ll then assign human-friendly names to Pods, explore various Kubernetes entities and functions, and discover when to use them. As you work through the chapters, this Kubernetes book will show you how you can make full-scale use of Kubernetes by applying a variety of techniques for designing components and deploying clusters. You’ll also get to grips with security policies for limiting access to certain functions inside the cluster. Toward the end of the book, you’ll get a rundown of Kubernetes advanced features for building your own controller and upgrading to a Kubernetes cluster without downtime. By the end of this workshop, you’ll be able to manage containers and run cloud-based applications efficiently using Kubernetes.
Table of Contents (20 chapters)
Preface

Probes/Health Checks

A probe is a health check that can be configured to check the health of the containers running in a pod. A probe can be used to determine whether a container is running or ready to receive requests. A probe may return the following results:

  • Success: The container passed the health check.
  • Failure: The container failed the health check.
  • Unknown: The health check failed for unknown reasons.

Types of Probes

The following types of probes are available for us to use.

Liveness Probe

This is a health check that's used to determine whether a particular container is running or not. If a container fails the liveness probe, the controller will try to restart the pod on the same node according to the restart policy configured for the pod.

It's a good idea to specify a liveness probe when we want the container to be terminated and restarted when a particular check fails.

Readiness Probe

This is a health check that's used...